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Subject: Re: [PATCH v4 04/14] x86/rtc: replace paravirt rtc check with
 platform legacy quirk
To: Juergen Gross <jgross@suse.com>, "Luis R. Rodriguez" <mcgrof@kernel.org>,
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From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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Date: Fri, 8 Apr 2016 08:37:44 -0400
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On 04/08/2016 03:59 AM, Juergen Gross wrote:
> On 08/04/16 09:36, Luis R. Rodriguez wrote:
>> On Fri, Apr 8, 2016 at 12:13 AM, Juergen Gross <jgross@suse.com> wrote:
>>> On 08/04/16 08:56, Luis R. Rodriguez wrote:
>>>> On Thu, Apr 7, 2016 at 11:38 PM, Juergen Gross <jgross@suse.com> wrote:
>>>>
>>>> Okay. Another idea (not sure whether this is really a good one):
>>>>
>>>> Add X86_SUBARCH_XEN_DOM0. As hardware_subarch is 32 bits wide I don't
>>>> think the number of subarchs is a scarce resource. :-)
>> This would mean bumping the x86 boot protocol, we shouldn't take that
>> lightly, but given that in this case the new subarch would really only
>> be set by the kernel (or future loaders for perhaps HVMLite) I'd think
>> this is not such an intrusive alternative.
> I think adding an own subarch for dom0 isn't that bad. It really is
> different from domU as dom0 has per default access to the real hardware
> (or at least to most of it).

Can we do this (overwrite quirks) in x86_init_ops.arch_setup? I'd really 
like to avoid adding a what essentially is a sub-subarch.

-boris